#include<iostream>
#include<vector>
#include<string>
#include<algorithm>
using namespace std;

class Solution {
public:
	bool searchMatrix(vector<vector<int>>& matrix, int target) {
		for (auto& row : matrix) {
			auto it = lower_bound(row.begin(), row.end(), target);
			if (it != row.end() && *it == target)
				return true;
		}
		return false;
	}
};

int main() {
	Solution s;

}